Electric switch



Sept. 17, 1929. v, l TRIER I 1,728,579

ELECTRIC SWITCH Filed Sept. 7, 1927 2 Sheets-=Sheet 1 Sept. 17, 1929. v, TRIER 1,728,579

ELECTR IC SWITCH Filed Sept. 1927 2 Sheets-Sheet 2 Patented Sept. 17,1929

VERNON ANTHONY TRIER, OF LONDON, ENGLAND ELECTRIC SWITCH Application filed September 7, 1927, Serial No. 218,031, and in Great Britain September 17, 1926.

This invention relates to electric switches of the kind comprising two disc-like or annular contact members arranged in parallel planes one above the other, one of these contact members being mounted on a resilient support which enables it to be rocked so as to make contact with the other contact member. The object of the invention is to provide an improved switch of the above type particularly but not exclusively applicable to the horn circuit of a motor road vehicle and adapted to be operated, for example, by depressing an auxiliary wheelrim mounted adjacent to and concentric with the rim of ,15 the steering wheel of the vehicle.

According to the present invention the flexible support for the movable contact member is formed of rubber "or other re silient insulating'material which will nor- 2e mally maintain the two contact members apart but will enable one of such members to be rocked into engagement with the other when the switch is to be closed. Thus the rubber or like member serves both as an insulator between the contact members and as a spring tending to separatethe two contact members.

The invention may be carried into practice, in various waysbut three alternative constructions of switch according to this invention suitable for losing the horn circuit of a motor road vehicle are illustrated by way ings, in which Figure 1 is a side elevation partly in section showing one form of switch secured to the vehicle steering wheel,

Figure 2 is a section on an enlarged scale through the annular contact members and 4a resilient insulating member constituting the switch shown in Figure 1,

Figure 3 is a side elevation partly in section showing an alternative form of switch according to this invention as applied to a 45. steering wheel, p

Figure 4 is a longitudinal section through the switch shown in Figure 3,

Figure 5 is an elevation partly in section of another alternative form of switch, and

Figure 6 is a section on an enlarged scale of example in the accompanying drawaround the groove A in the inner contact through the fixed and movable members constituting the switch shown in Figure 5.

In the construction illustrated in Figures 1 and 2 the switch comprises an annular inner contact member A adapted to be secured to the vehicle steering wheel B by means of clips or the like C. Surrounding the upper portion of the member A and formed so that it extends inwards over the upper edge of this member is an outer annular contact (so member D. Formed in the portions of the contact members A and D which overlap are grooves ADD which together form an annular recess between the two contact members in which is accommodated a tubular rubber or like resilient insulating member E. The member E thus serves not only to insulate the contact members from one another and normally to maintain the contact member D out of engagementwith the contact member A but also to prevent the contact member D being detached from the contact member A. It will thus be seen that the annular member E is held under compression in the recesses in themembers A and D and serves as the sole operative connection between these parts to prevent their being C0111: pletely se arated, yet allow further compression w en one contact member is rocked into engagement with the other.

The contact member A may if desired be provided with contact points A on its-upper edge as shown to ensure proper contact being made with the contact member B while terminals A D are conveniently provided re spcctively on the contact members A and D for connecting these members respectively to one of the horn terminals and one of the battery terminals.

In the construction shown in Figures 1 and 2 the member E is conveniently formed as a plain length of tubing and the contact members A and D and member E may be assembled by stretching the tube E tightly member A so that this tube is flattened, the ends of the tube being drawn through two holes A passing radially through the con tact member as shown. The lower edge of the contact member D is then passed over ice whereupon the tube contracts in length and expands. laterally into contact with the groove D in the outer contact member D. If after the ends of the tube have been released, these still project through the holes A", they may be cutoff.

Alternatively to the above method of assembling the parts of the switch, the following method may be employed, the rubber tube in this case being formed either as a plain length of tubing or as a complete ring. In carrying out this alternative method of assembly the tube E is placed in position in the groove A in the inner. contact member A which then has one side thereof placed within the outer contact member D so that a portion of the tube .is in position between the two contact members. The inner contact member is then gradually tilted into its correct position within the outer contact member, the' tube being stretched locally during this operation where it is being passed over the lower'edge of the Outer contact member into the grbove D therein. Thus this method of assembly may be likened to the fitting of a pneumatic tyre to a wheel rim in that'a portion of the tubular insulating member is first placed in position and then the rest is gradually worked into place.

In the construction illustrated in Figures 3 and 4 the switch comprises a member F formed of insulating material and secured to the steering wheel boss or post G by a bolt H passing through an upper disc H a hollow distance piece or sleeve H and a lower disc H The member F supports a fixed annular contact member J having a terminal J adapted to be connected for example to one terminal K of a-horn indicated at 'K. Surrounding the sleeve H and clamped between the upper and lower discs H and H is a ring L of rubber or other resilient insulating material, the outer edge of which has mounted thereon the boss M of an auxiliary switch operating wheel M The boss M carries a movable contact ring N held in position by means of a spring ring or the like N and serving to maintain the boss M in position on the rubber ring L. The boss M is formed of electro-conducting material and carries a terminal M which is connected to one terminal of a battery indicated at O in Figure 2 the other terminal of which is connected to the second terminal K ofthe horn K as shown.

It will be seen that by depressing the rim M of the wheel M at any point, the rubber ring L canb'e flexed and the movable contact member N brought into contact with the fixed contact member J thus completing the horn circuit, the wheel 1 and movable contact member N being returned to the normal inoperative position by the resilience of the rubber ring L when the rim M is released.

In the construction illustrated in Figures 5 and 6 the switch comprises an annular member P adapted to be secured to the steering wheel 'for example by .members Q clamping it to the spokes. Mounted on theupper surface of the member P is a metallic contact ring or a series of contact segments R between which and the member P is gripped the inner edge of a rubber rlng or serles of .rubber segments S, the number of segments being for example four or five. The outer edge of the rubber ring or of each rubber segment S is clamped by a ring T to a mov able contact member U conveniently in the form of a wheel rim. Terminals R and U are provided respectively on the contact members R- and U as shown. With this arrangement it will be seen that the rim U which also constitutes the movable contact member can be rocked by applying pressure to it at any point so as to make contact between it and the fixed contact member. or members R and thus close-the switch to complete the horn or other circuit. construction shown in Figures 1 and 2 and in Figures '3v and 4 the rim U is returned to its normal or neutral position automatically when it is released by reason of the I As in the to insulate the contact members R and U from one another.

It is to be understood that the constructional details of the switch may be varied considerably according to the purpose for.

which the switch is intended or to suit individual requirements without eparting from this invention. Further although the invention is particularly applicable to switches for closing the horn or other circuits on motor road vehicles, it may also be applied where convenient to switches for other purposes.

What I claim as my invention and desire to secure by Letters Patent is 1. An electric switch including in combination two coaxial contact members, at least a portion of one member lying within the other member, said members having opposed recesses formed in these overlapping portions and resilient material disposed radially between the two members in the recesses and serving normally to maintain the contact members out of contact but to permit one to be rocked into engagement with the other when desired.

2. An electric switch including in combination two coaxial contact members, at least a portion of one member lying within the other member, said members having opposed recesses formed in the overlapping portions, and resilient insulating material compressed radially between the two members in the recesses thereby to maintain the contact members out of contact and to serve as the operative connection between them to pre vent their. being completely separated yet allow further compression when one contact member is rocked into engagement with the other.

3. An electric switch including in combination two coaxial contact members, at least a portionof one member lying within the other member, said members having opposed annular recesses formed in the overlapping portions, and a length of resilient insulating material disposed in the recesses so as to lie radially between the two contact members and serve to maintain them normally out of contact but to permit one contact member to be rocked into engagement with the other when desired.

4. An electric switch including in combination two coaxial contact members, at least a portion of one member lying within the other member, said members having opposed annular recesses formed in the overlapping portions, and a length of resilient insulating material disposed in the recesses free from positive connection with either contact member so as to lie radially between the two con tact members and serve not onl normally to maintain them out of contactl) serve as the sole operative connection between the contact members thereby to prevent their being completely-separated but enable one contact member to be rocked into engagement with the other when desired.

ut also to VERNON ANTHONY TRIER.

v 5. An electric switch including in combination two coaxial contact members, at least a portion of one member lying within the other member, said members having opposed annular recesses formed in the overlapping portions, and a length of rubber tubing disposed in the recesses so as to lie radially between the two contact members and serve. to mamtain'them normally out of contact but to permit one contact member-o to be rocked into engagement with the other when desired. 7

6. An electric switch including in combination two coaxial contact members, at least a portion of one member lying-within the other member, said members having op posed annular recesses formed in the overlapping portions, and a length of rubber tubing disposed in the recesses without being positively connected to either contact memher so as to lie radially between the two contact members and serve not only normally to maintain them out of contact but also to serve as the sole operative connection between the contact members and 

